The present invention relates in general to a mixing or proportioning valve and refers more particularly to a ball-type single handle valve for mixing hot and cold water and for controlling the volume of flow through the valve.
U.S. Pat. No. 3,809,124 discloses a single handle mixing valve that comprises a body, ball-shaped control member, a liner and diaphragm. One object of this invention is to provide an improved mixing valve which is characterized by a long operating life.
One problem with the existing valve structure is that the flow through the valve is somewhat restricted. This occurred primarily because it was possible to tighten the liner too tightly against the diaphragm. Accordingly, one object of the present invention is to provide for improved flow through the valve by limiting the position of the liner and diaphragm to the body.
Another problem that was encountered with the prior art structure was wear of the diaphragm especially about the nipples of the diaphragm.
Accordingly, another object of the present invention is to provide an improved mixing valve structure that will reduce wear of the diaphragm.
A further object of the present invention is to provide an improved construction for the ball-shaped control member.
Still another object of the present invention is to provide an improved porting arrangement for the inlet ports that will enhance the sealing characteristics of the valve.
Another object of the present invention is to provide an improved mixing or proportioning valve that has good sealing characteristics, that can be manufactured preferably using mostly plastic parts and at a reasonable cost, that is easy to maintain that has an easily replaceable diaphragm, and that has a long cycle life.